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The study analyzed three genotypes of industrial hemp, Cannabis sativa L., under the aspect of fiber productivity indices in relation to plant parameters. The study took place in ARDS Lovrin, Romania. The genotypes Silvana (control), Teodora and Lv-300 were evaluated. The experiment took place under the conditions of a chernozem type soil, non-irrigated system. Several parameters and indexes were analyzed: total plant weight (TPW), stem length (SL), inflorescence length (IL), technical length (TL), middle stem diameter (MSD), dry sample weight (DSW), dry fiber content (DFC), pure fiber weight (PFW), and technical fiber (TF). The DFC index showed positive correlations with SL (r=0.708***), with MSD (r=0.712***), with DSW (r=0.739***), with TPW (r=0.546**), and with TL (r=0.399*). The PFW index showed negative correlations with TPW (r=-0.493**) and with DSW (r=- 0.373*). Technical fiber (TF) showed very strong, positive correlations with PFW (r=0.999***) and negative correlations with other parameters (e.g. with TPW, r=-0.493**, with DSW, r=-0.373*). From the comparative analysis of Teodora in relation to Silvana, average values TFT=31.355 (Teodora) and TFS=28.388 (Silvana) resulted, and the differences showed statistical certainty (t=2.5948, with p=0.013; U=72, p=0.0045; p<0.05). From the comparative analysis of Lv-300 in relation to Silvana (control), mean values TFT=29.357 (Lv-300) and TFS=28.388 (Silvana) resulted, but the differences did not show statistical certainty (t=0.763, with p=0.451; U=117, p=0.158; p>0.05). The regression analysis led to equations and graphic models that described the variation of fiber productivity indices in relation to plant biometric parameters. [ABSTRACT FROM AUTHOR]

The study comparatively analyzed the productivity level of 48 commercial sunflower hybrids, under the specific crops conditions of the Western Plain of Romania. The field experiment took place within ARDS Lovrin, agricultural year 2021-2022. 27 hybrids from the Imazamox class (IH; IH1 to IH27) and 21 hybrids from the Tribenuron Methyl class (TMH; TMH1 to TMH21) were cultivated. The cultivation of the 48 hybrids was carried out under the conditions of a chernozem type soil, and non-irrigated system. In the case of Imazamox class hybrids (IH), the production varied between 2012.47 kg ha-1 (IH4) and 3,545.08 kg ha-1 (IH1, and IH23). In the case of hybrids from the Tribenuron Methyl class (TMH), production varied between 2,437.64 kg ha-1 (TMH17) and 3,713.15 kg ha-1 (TMH4, and TMH19). Based on the production data recorded for each hybrid, the average value was calculated for each class of hybrids (IH-Avg=3,038.13 kg ha-1, TMH-Avg=3,287.98 kg ha-1). In order to verify whether there are differences between the two groups IH (N=27) and TMH (N=21) regarding the recorded production, the Null Hypothesis (H0) was defined. The application of the t-test for Equality of Means, led to the value of t=2.302 with p=0.02. Additionally, the non-parametric Mann-Whitney test was applied. The U=180 value with p=0.03 also indicated significantly different productions between the related series of the two classes of hybrids. The increase in production (kg ha-1, %) was calculated for each class of hybrids (ΔIH, ΔTMH) and a classification was made within each class. The cluster analysis facilitated the clustering of sunflower hybrids in relation to the recorded production. [ABSTRACT FROM AUTHOR]

The aim of the study was to use a technique based on aerial images (UAV) to wheat production estimation. The images were taken with the drone (UAV, DJI Phantom 4) at different image capture heights (ICH), in the range of 1.5 - 50 m from the ground level, and resulted in 18 sets of images (trials, T). The resized images (crop image, 1,000 x 2,000 pixels) were analyzed and the information for RGB color parameters was obtained. Very strong correlations were recorded between color parameters R and G (r=0.993), as well as between these two color parameters and ICH (r=0.940 in the case of R, respectively r=0.918 in the case of G). Based on the trials distribution in the PCA diagram and in the CA dendrogram, 14 trials (T1, T3-T6, T8-T10, T12-T14, T16-T18) were selected for Training & model construction (Tmc), and four trials (T2, T7, T11 and T15) for were used for Testing & model validation (Tmv). Through the regression analysis, a wheat production estimation model was obtained based on RGB parameters under statistical safety conditions (R2=0.999, p<0.001). Flowchart diagram of process was proposed for the present study, and the work process, respectively the obtained models can be adapted for various other agricultural crops. [ABSTRACT FROM AUTHOR]

Phomopsis mali Roberts (Phomopsis fruit tree canker) is a fungus that infects the fruit tree trunks, branches and sprigs. There were described more than 60 species of Phomopsis. Every of the species is identified in general after the size of the conidia and after the host from which was isolated, the precise identification being sometimes difficult. Phomopsis is a fungus that can produce serious damages in production because it affects the fruitful sprigs. On the other hand, in case of massive attacks it can lead to the fruit trees decline. In the young orchards cultivated in ecologic super-intensive system, the young trees can die in the case of severe infections. The purpose of this research was to identify the Phomopsis fungus in an ecologic super-intensive apple orchard from Arad County (western Romania), in the first two years after the plantation. The biological material used was consisting in six samples sets (sprigs, stems, branches and roots) collected from four apple varieties (Primiera/M9, Crimson Crisp/M9, Golden Orange/M9 and GoldRush/M9). The identification of the disease and of the pathogen was done using visual and laboratory methods. In laboratory was identified the fungus with the humid chamber method and by placement of diseased tissue samples on culture medium followed by incubation at 23 - 24oC for seven days. The branches, sprigs and stems were analysed at stereomicroscope too. Under the cracked bark were identified numerous pycnidia of black colour and pear shaped, specific to the Phomopsis mali fungus. There were noticed young and old fructifications, the old ones were from the previous year or even from the precedent years. The obtained results after the visual analysis of the trees in the orchard and after the laboratory analyses highlighted the presence of the fungus Phomopsis mali. There were highlighted at the microscope the alpha and beta conidia, typical for this fungus. In the orchard all the trees were presenting symptoms specific to the Phomopsis fruit tree canker. The trees covered with numerous canker lesions were died. At the assessment time the dead trees rate on varieties was the following: Primiera – 16.5%, Crimson Crisp – 1.7%, Golden Orange – 16.1%, and Gold Rush – 17.2%. From all the analysed apple varieties only Crimson Crisp had reacted well to the attack of the Phomopsis mali fungus. [ABSTRACT FROM AUTHOR]